1. Field of the Invention
The invention is directed to a sports boot having a base or lower part, referred to as a shell base, and an upper part, referred to as a collar. More particularly, the invention is directed to a device that allows a blocking and an unblocking of the collar relative to the shell.
2. Background and Other Information
Devices of the aforementioned type are known in the prior art. For example, French Patent Application Publication No. 2 661 076, and family member U.S. Pat. No. 5,136,794, disclose a ski boot equipped with such a device.
In such boot, the blocking device is located in the rear zone of the boot and interacts between the collar portion and the shell base portion of the boot via a rocking element mounted on a pivot pin. The rocking element, affixed to the collar, in particular by means of its pivot, is provided to be capable of alternatively occupying two predetermined angular positions, one to oppose the pivoting of the collar with respect to the shell base in the front-to-rear direction, and the other to allow the collar to pivot freely in that direction. To this end, the rocking element has a support zone at the end of a free arm that extends downward on the side of its pivot and in correspondence with an abutment with which the shell base is provided. Thus, for a given angular position of the rocking element, its free arm cooperates with the abutment of the shell base via its support zone and pivotally blocks the collar in the front-to-rear direction; conversely, for another given angular position of the rocking element, its free arm retracts from the abutment of the shell base, and allows the collar to pivot in the front-to-rear direction.
The blocking device of this boot is satisfactory but has a mechanical weakness in the area of the pivot of the rocking element. Indeed, because the rocking element does not include a counter-support on its free arm, all of the forces to which the free arm is subjected are entirely taken up by its pivot pin. However, due to its cylindrical shape and its small diameter, the pivot pin offers resistance and a reduced support surface in particular in the location of its ends, which are encased in the upper, on both sides of the rocking element. Also, taking into account the intensity and the repeated occurrence of the forces directed in the front-to-rear direction during the sporting activity, it is often noted that the ends of the pivot and their housings become oval in the collar, which can be the origin of the breakage of the pivot pin in certain cases. Further, the intensity of the forces in the front-to-rear direction forces the pivot pin to bend until causing its permanent deformation, in particular when the collar of the boot has a large housing on the side opposite the support zone of the free arm of the rocking element, which cooperates with the abutment of the shell base.
Furthermore, the blocking device described in the aforementioned documents is particularly bulky, because the collar includes an enlargement, or cap, that covers the device.
Finally, the pivot pin is in the center of the rocking element, i.e., halfway between the support zone and the upper portion which is connected to the means allowing for the actuation. Consequently, the amplitude of movement of the actuating means must be equal to that which is necessary for disengaging from the support zone. This results, among other things, in making the device bulky.